Extensive air showers are a very unique phenomenon. In the more than six decades since their discovery by Auger and collaborators we have learned a lot about these extremely energetic events and gained deep insight into high-energy phenomena, particle phy
I.- Introduction, Facts and Phenomenology.- Shower Detection Methods and Basic Event Reconstruction.- Hadronic Interactions and Cascades.- Electromagnetic Interactions and Photon-Electron Cascades.- Muon and Neutrino Interactions.- Longitudinal Developmen